MJA 199 (S36

Supplement

David CunningtonMB BS, MMedSc, FRACP,

Sleep Physician andDirector1

Moira F Junge BA, BAppSc(Hons), DPsych

(Health),Psychologist1

Antonio T FernandoMD, FRANZCP, Senior

Lecturer2

1 Melbourne Sleep DisordersCentre, Melbourne, VIC.

2 Department ofPsychological Medicine,University of Auckland,

Auckland, NZ.

david.cunnington@msdc.com.au

MJA 2013; 199: S36–S40doi: 10.5694/mja13.10718

Online first 17/10/13

Insomnia: prevalence, consequences and effective treatment

The Medical Journal of Australia ISSN:0025-729X 21 October 2013 199 8 36-40©The Medical Journal of Australia 2013www.mja.com.auSupplement

usually begun to behave and ently, in ways that are maladapsleep difficulties.8 The long-termone of relapse and remissionwhich continues well after the astances have passed. Thereforeneeds to match this, with a chr

8) · 21 October 2013

• Insomnia is common and can have serious consequences, such as increased risk of depression and hypertension.

• Acute and chronic insomnia require different management approaches.

• Chronic insomnia is unlikely to spontaneously remit, and over time will be characterised by cycles of relapse and remission or persistent symptoms.

• Chronic insomnia is best managed using non-drug strategies such as cognitive behaviour therapy.

• For patients with ongoing symptoms, there may be a role for adjunctive use of medications such as hypnotics.

Summary

nscalat

popuI

omnia is a very common disorder that has signifi-

nt long-term health consequences. Australian popu-ion surveys have shown that 13%–33% of the adultlation have regular difficulty either getting to sleep

or staying asleep.1,2 Insomnia can occur as a primarydisorder or, more commonly, it can be comorbid withother physical or mental disorders. Around 50% ofpatients with depression have comorbid insomnia, anddepression and sleep disturbance are, respectively, thefirst and third most common psychological reasons forpatient encounters in general practice.3 Insomnia doublesthe risk of future development of depression, and insom-nia symptoms together with shortened sleep are associ-ated with hypertension.4,5

Insomnia is defined in the fifth edition of the Diagnosticand statistical manual of mental disorders (DSM-5) as diffi-culty getting to sleep, staying asleep or having non-restorative sleep despite having adequate opportunity forsleep, together with associated impairment of daytimefunctioning, with symptoms being present for at least 4weeks.6 Having a sleep experience that does not meet ourexpectation, such as with some transient awakenings butwith good daytime functioning, does not constituteinsomnia.

Acute versus chronic insomnia

Acute insomnia is defined as sleep disturbance meetingthe DSM-5 definition of insomnia, but with symptomsoccurring for less than 4 weeks.6 Generally, acute insom-nia is triggered by precipitating events such as ill health,change of medication or circumstances, or stress. Oncethe precipitating event passes, sleep settles back to itsusual pattern. Hence, treatment for acute insomnia isfocused on avoiding or withdrawing the precipitant, ifpossible, and supporting the acute distress of not sleep-ing with short-term use of hypnotics if symptoms aresignificant. This is the usual approach in primary care,with 95% of general practitioner consultations for insom-nia resulting in the prescription of a hypnotic, usually abenzodiazepine.7

However, if patients have repeated episodes of acuteinsomnia or ongoing comorbidities, insomnia symptomscan persist and evolve into chronic insomnia, whichrequires a different treatment approach. Once peoplehave had difficulty sleeping for over 4 weeks, they have

think about sleep differ-tive and perpetuate their course is then generally

rather than resolution,9

cute precipitating circum-, the treatment approachonic disease management

model educating and upskilling patients on how best tomanage their insomnia symptoms over time. Health care

providers need to see insomnia as a chronic illness andemphasise the role of strategies to prevent relapses,rather than focusing on treatment of acute episodes orcrises.

Assessment and diagnosis of insomnia

The assessment and diagnosis of insomnia is formulatedmainly from a systematic sleep history. To assist inestablishing premorbid baseline sleeping patterns andformulating treatment goals, clinicians must ask patientsabout their typical sleeping pattern before they developedinsomnia.

Insomnia assessment involves understanding thepatient’s typical sleep pattern at night and over a timeframe of weeks to months. Therefore, part of the sleepassessment is asking for the patient’s narrative of typicalbedtime, time taken to fall asleep after lights out (sleeplatency), frequency and rough duration of awakenings inthe middle of the night, and what time the patient getsout of bed. Are there times when sleep returns to normal?Was there an initial trigger or did the symptom arisespontaneously? Was it related to a period of stress,anxiety or depression? Did it start during childhood andcontinue thereafter? Are there lifestyle factors contribut-ing to insomnia, such as too much caffeine or exerciselate in the day, television or pets in the bedroom, or use ofalcohol or nicotine? Knowing the patient’s cognitions,beliefs and worries about sleep, which are often apparentin the language and emotion used when they describetheir sleep, can assist in the formulation of specificbehavioural and calming approaches to assist with sleep.

It is important to assess the effects of poor sleep on thepatient. Common daytime consequences include moodlowering, irritability, poor memory, fatigue, lack of energyand general malaise. These can manifest as work absent-eeism, with insomnia being one of its leading medicalcauses.10 It is also imperative to ask for risky con-sequences of insomnia, including accidents and sleepi-ness while driving.

Sleep disorders

Identifying the body clock type of the patient is crucialin excluding circadian rhythm disorders. A commonlyundiagnosed condition, delayed sleep phase disorder is abody clock variation where the patient is biologicallyinclined to go to sleep much later than usual (typicallyafter midnight), yet generally sleeps well after sleeponset, with a natural wake time that is much later thanfor most people and is often incompatible with normalschool or work start times.

It is also important to look for comorbid conditionsthat can present with insomnia, such as depression andanxiety, chronic medical conditions, and other sleepdisorders. Comorbid conditions have a bidirectionalrelationship with insomnia, with each influencing orexacerbating the other and requiring concurrent assess-ment and management. The Auckland Sleep Question-naire, a validated sleep screening questionnaire inprimary care, is one tool that can assist in identifyingthese disorders.11 Other validated questionnaires such asthe Insomnia Severity Index can help to document theseverity of patients’ symptoms and assess their responseto treatment.12

Since many people with insomnia overestimate theirsleep disruption and underestimate actual sleep time, a2-week sleep diary is a very helpful assessment tool as itassists the sleep clinician to get a more accurate snapshotof sleep compared with a pure verbal account.13 Forsome, a sleep diary is revealing in that they realise thatthey do get some sleep, albeit fragmented or superficial.This can provide the basis for discussion. There areseveral downloadable sleep diaries online — for example,http://yoursleep.aasmnet.org/pdf/sleepdiary.pdf. Ifpatients have difficulty completing a sleep diary, or thereis significant misperception of sleep suspected, actigra-phy (using a device worn on the wrist to monitor sleep–wake cycles) can be used to objectively measure sleep.

Although an overnight sleep study or polysomnogra-phy is not routinely indicated in diagnosing insomnia, itcan be helpful in diagnosing several conditions, includingobstructive sleep apnoea, sleep-related movement disor-ders, parasomnias, or insomnias that are treatment-resistant.13 A routine physical and mental status exam-ination can give clues regarding comorbid medical and ormental health conditions. Other tests including labor-atory and radiographic procedures are not routinely indi-cated in chronic insomnia.13

Non-pharmacological treatment of insomnia

Cognitive behaviour therapy aimed at treating insomnia(CBT-i) targets maladaptive behaviour and thoughts thatmay have developed during insomnia or have contributedto its development. CBT-i is considered to be the goldstandard in treating insomnia, with effect sizes similar toor greater than those seen with hypnotic drugs and,unlike with hypnotics, maintenance of effect after cessa-tion of therapy.14,15 These effects are seen in both primaryand comorbid insomnia.16

The implementation of individual face-to-face CBT-i istypically delivered by a trained health professional, which

makes it expensive, labour intensive and thereforebeyond the reach of many. Patients with insomnia areeligible for Medicare rebates for psychological treatmentif they are referred under the Chronic Disease Manage-ment or Better Access to Mental Health Care initiatives.Telephone and online delivery of CBT-i have been shownin clinical trials to be as effective as face-to-face CBT-i.17,18

While these different treatment delivery models have thepotential to markedly improve access to CBT-i, they needto be investigated further with respect to their long-termreliability and effectiveness. They might be best used aspart of a stepped-care approach.19 Some patients mayneed little guidance, while others may need more per-sonal treatment and guidance.

CBT-i consists of five major components: stimuluscontrol, sleep restriction (also known as sleep consolida-tion or bed restriction), relaxation techniques, cognitivetherapy and sleep hygiene education (Box). Typically,CBT-i is delivered in four to 10 sessions, either individu-ally or in a group setting, ideally involving four to eightparticipants.

Stimulus control is a reconditioning treatment forcingdiscrimination between daytime and sleeping environ-ments.20 For the poor sleeper, the bedroom triggersassociations with being awake and aroused. Treatmentinvolves removing all stimuli that are potentially sleep-incompatible (reading, watching television and use ofcomputers) and excluding sleep from living areas. Theindividual is instructed to get up if he or she is not asleepwithin 15–20 minutes, or when wakeful during the nightor experiencing increasing distress, and not return to beduntil feeling sleepy.

Sleep restriction relates to better matching the timespent in bed to the average nightly sleep duration.21

Patients keep a sleep diary to determine average sleepduration. They are then allowed a period of time in bedequal to this plus 30 minutes, and set a regular arisingtime. As some patients can underperceive the amount ofsleep, the time in bed should never be set at less than 5hours. As sleep becomes more consolidated, the length oftime in bed can be gradually increased in 15–30 minuteincrements. This effective intervention induces naturalsleepiness (reduced time in bed) and gives the individuala sense of assurance that bed is now a safe place to sleep.Bed restriction has recently been shown to be an effectiveintervention in primary care.22

Relaxation techniques include progressive relaxation,imagery training, biofeedback, meditation, hypnosis andautogenic training, with little evidence to indicate superi-ority for any one approach. Patients are encouraged topractice relaxation techniques throughout the day andearly evening. Even a few minutes two to four times a dayis useful. A last-minute relaxation attempt minutes beforesleep will not work miracles. Muscular tension and cogni-tive arousal (eg, a “chattering” mind) are incompatiblewith sleep. At the cognitive level, these techniques mayact by distraction. Relaxation reduces physical and mentalarousal but is less effective as a stand-alone treatmentand is better used in combination with other treatmentinterventions.

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Cognitive therapy involves enabling the patient torecognise how unhelpful and negative thinking aboutsleep increases physiological and psychological arousallevels. Setting aside 15–20 minutes in the early part of theevening to write down any worries, make plans for thefollowing day and address any concerns that might ariseduring the night allows the day to be put to rest. It ishelpful to challenge thoughts that arise at night with “Ihave already addressed this and now I can let go of it!”.“Time out” — some form of soothing activity before bed— can be useful in reducing arousal levels. Thought-stopping attempts or blocking techniques, such asrepeating the word “the” every 3 seconds, occupy theshort-term memory store (used in processing informa-tion), potentially allowing sleep to happen. Cognitiverestructuring challenges unhelpful beliefs, such as “if Idon’t get enough sleep tonight, tomorrow is going to be adisaster”, which maintain both wakefulness and help-lessness. Another cognitive and behavioural technique isparadoxical intention. Clients are encouraged to put theeffort into remaining wakeful rather than trying to fallasleep (decatastrophising), thereby strengthening thesleep drive and reducing performance effort.14

There is limited evidence to suggest that, on its own,sleep hygiene is efficacious.14 However, it is an essentialcomponent of CBT-i and involves “cleaning up” orimproving an individual’s sleep environment and behav-iour to promote better sleep quality and duration.23

Mindfulness and insomnia

In recent years, the technique of mindfulness has becomeincreasingly popular and is likely to be efficacious inhelping to promote sleep by reducing cognitive andphysiological arousal. Mindfulness treatment interven-tions have demonstrated statistically and clinically signif-icant improvements in several night-time symptoms ofinsomnia, as well as reductions in presleep arousal, sleep

effort and dysfunctional sleep-related cognitions.24 Inmany cases, mindfulness is combined with CBT-i.24,25 Asan adjunct to CBT-i, it can be used for psychoeducation tohelp the client develop a more functional schematicmodel of sleep and for dealing with sleeplessness, includ-ing the detrimental role of hyperarousal. Typically, thechattering mind is focused on past or future events,whereas mindfulness emphasises being non-judgemen-tal in the present, which potentially can reduce mindactivation.

Bright light exposure (natural or artificial)

Educating the patient about sleep and the importance ofbright light is an important aspect of treating insomnia.Good objective information about sleep, sleep loss andthe body clock are helpful starting points for self-man-agement. Bright light is a potent synchroniser for humancircadian rhythm. In particular, morning light, which canbe combined with exercise such as walking, can behelpful in consolidating night-time sleep and reducingmorning sleep inertia.26

Pharmacological treatment of insomnia

Although psychological and behavioural interventionsare indispensable and effective for most insomnia suffer-ers, some will still need the extra help from pharmacolog-ical agents. Current medications and natural productsused for insomnia include benzodiazepine-receptor ago-nists, melatonin and variants, antidepressants, antipsy-chotics and antihistamines.

Hypnotic drugs that act on the -aminobutyric acidreceptor include benzodiazepines, such as temazepam, aswell as the benzodiazepine-receptor agonists, such aszopiclone and zolpidem. Medications of this group havebeen studied in randomised controlled trials, with effi-cacy over 6 months27 and longer in open-label exten-

Cognitive behaviour therapy for insomnia

Intervention General description Specific instructions

Stimulus control BED = SLEEP. Set of instructions aimed at conditioning the patient to expect that bed is for sleeping and not other stimulating activities. Only exception is sexual activity. Aim is to promote a positive association between bedroom environment and sleepiness

Go to bed only when sleepy/comfortable and intending to fall asleep. If unable to sleep within what feels like 15–20 minutes (without watching the clock), leave the bed and bedroom and go to another room and do non-stimulating activity. Return to bed only when comfortable enough to sleep again. Do not read, watch television, talk on phone, pay bills, use electronic social media, worry or plan activities in bed

Sleep-restriction therapy

Increases sleep drive and reduces time in bed lying awake. Limits the time in bed to match the patient’s average reported actual sleep time. Slowly allows more time in bed as sleep improves

Set strict bedtime and rising schedule, limited to average expected hours of sleep reported in the average night. Increase time in bed by 15–30 minutes when the time spent asleep is at least 85% of the allowed time in bed. Keep a fixed wake time, regardless of actual sleep duration

Relaxation techniques Various breathing techniques, visual imagery, meditation Practise progressive muscle relaxation (at least daily). Take shorter relaxation periods (2 minutes) a number of times per day. Use breathing and self-hypnosis techniques

Cognitive therapy Identifies and targets beliefs that may be interfering with adherence to stimulus control and sleep restriction. Uses mindfulness to alter approach to sleep

Unhelpful beliefs can include overestimation of hours of sleep required each night to maintain health; overestimation of the power of sleeping tablets; underestimation of actual sleep obtained; fear of stimulus control or sleep restriction for fear of missing the time when sleep will come

Sleep hygiene education

Emphasises environmental factors, physiological factors, behaviour, habits that promote sound sleep

Avoid long naps in daytime — short naps (less than half an hour) are acceptable. Exercise regularly. Maintain regular sleep–wake schedule 7 days per week (particularly wake times). Avoid stimulants (caffeine and nicotine). Limit alcohol intake, especially before bed. Avoid visual access to clock when in bed. Keep bedroom dark, quiet, clean and comfortable

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Sleep disorders

sions.28 Many doctors avoid prescribing medications fromthis family, mainly because of concern regarding depend-ence and tolerance. However, long-term trials of eszopi-clone (not available in Australia) and extended-releasezolpidem have shown sustained response with no toler-ance and dependence after 6 months of daily use.27-29

Despite these findings, the concern remains that thereare vulnerable patients who may become dependent onhypnotic drugs. To limit the risk of tolerance and depend-ence, the prescriber can instruct the patient to use themedication on a scheduled basis; for example, only onalternating nights, or three times a week and at thelowest effective dose possible for a limited time (ie, amonth).27 Zolpidem has been associated with parasom-nias, so clinicians need to warn patients about unusualsleep behaviours as a side effect. Sudden discontinuationof this class of medications can result in a reboundinsomnia that can be mitigated by a gradual taper.

Despite the similarity in the mode of action andpharmacokinetics of these agents, patients react differ-ently to each product. Lack of response to one agent doesnot mean that others of the same group will not work.Similarly, an adverse effect of one does not mean thatothers will cause the same reaction. The decision whetheror not to prescribe hypnotics should rely on a careful risk–benefit analysis by both the doctor and the patient. Inaddition to the perceived risk of dependence and toler-ance, clinicians should consider the risks of untreatedinsomnia.

Melatonin has been shown to be effective in treatinginsomnia, particularly among people aged over 55years.30 However, melatonin is more effective as achronobiotic for treating body clock conditions like jetlagand delayed sleep phase disorder than as a treatment forchronic insomnia.31

Sedating antidepressants (eg, doxepin, amitriptyline,mirtazapine, trimipramine), sedating antipsychotics (eg,quetiapine, olanzapine) and antihistamines are used off-label as sleep medications, despite insufficient evi-dence.13,32,33 Many clinicians prefer prescribing thesemedications over hypnotics, because of perceived con-cerns regarding the risks of dependence and toleranceassociated with hypnotics, and despite antidepressants,antipsychotics and antihistamines also having seriousside effects including weight gain, anticholinergic sideeffects and diabetes. The decision to prescribe this groupof medications for insomnia should be based on a carefulrisk–benefit analysis, not solely on concerns regardingthe risks associated with hypnotics.

Among herbal and alternative medication choices fortreating insomnia, valerian has the most evidenceshowing possible mild improvements in sleep latency,with inconsistent effects on the rest of the objectivesleep parameters.13 Although valerian shows somepromise in improving sleep latency without side effects,the clinical trials are poorly designed and generally ofshort duration.34

Conclusion

Insomnia is complex and usually chronic by the time theindividual consults a health practitioner, with cognitive,behavioural and social factors involved in its mainte-nance. Simple instructions, such as avoiding stress, orshort-term use of hypnotics are usually not effective.CBT-i is an effective intervention with long-term efficacythat enables patients to better manage and live with theirinsomnia symptoms. The development of online deliveryof CBT-i markedly improves access to treatment and canbe readily used in primary care as first-line treatment formost patients, with specialised sleep services managingmore complex cases, those with ongoing symptoms andthose who require person-to-person care.Competing interests: David Cunnington has received payment for consultancy work, lectures and educational presentation development from BioCSL, and for lectures from Servier and Bayer Healthcare. Antonio Fernando has received educational grants and/or payment for lectures from BioCSL, Eli Lilly, MSD, Jannsen, Lundbeck and Sanofi.

Provenance: Commissioned by supplement editors; externally peer reviewed.

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